If using the tnsnames.ora file (by default, or by definition as identified in the sqlnet.ora file), the 12154 means the entry could not be found in that file.
XE = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = here)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = XE) ) ) DB11R2 = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = test88)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SID = orcl) ) )
I have installed Oracle 10g R2 Enterprise Edition so I do have netca.exe and have used it to configure the tsnames.ora file. I've also used net manager to configure the listener and net service name. The part that confuses me though is that I can't even create a database to begin with without getting the ORA-12154 error. Are all of these configurations needed before you even create a database?